what’s in a name: non-idiomatic improvisation

Is any improvised music really idiomatic?

I’ve already remarked on the label ‘non-idiomatic improvisation’ in connection with ‘pan-idiomatic improvisation’, and, in addition, in examining the term ‘free improvisation’, I’ve stated that ‘free improvisation’ could denote an “assortment of overlapping or unrelated things”, and to some, perhaps lesser, extent, this is also the case with ‘non-idiomatic improvisation.’ Also, in the same way that we can read the ‘free’ to denote an aspiration rather than an achievement, ‘non-idiomatic’ could denote an (unachievable) aim.
Having already iterated the corresponding problems and pitfalls, I don’t want to rehearse them here in the context of this new term. I do, however, want to ask whether improvisation can, under any circumstance, be idiomatic. I am not asking if non-idiomatic improvisation is possible (analogous to the question of whether an improvisation can be truly free), I’m asking if ‘idiomatic improvisation’ is a misnomer.

According to my computer’s online dictionary, idiom is “a characteristic mode of expression in music or art.” Hmm… not sure that helps here. So, beyond definitions of idiom that assume communication or expression (thorny parameters that likely end up in the ‘I-know-it-when-I-see-it’ domain), what might be a pragmatic, workable definition of ‘idiom’? I’ll propose, for the purposes of this discussion, that idiom is the mechanism via which the intricate and contingent nexus of expectations play out through performance. Listening to a performance, if expectations are met, we have something that is idiomatic, perhaps even stereotypical.
Fine, fine, fine… But in practice, how is an audience member processing, and judging, these chains and chains of probabilities? In practice, how are you even to know which set of probabilistic archetypes—which idiom—is in operation? And how does this all play out in the practice of improvisation?
Take a guitarist, an improviser. Just that choice of instrument comes with so much cultural baggage that an audience member, for all I know, is immediately calculating clouds of probable scenarios. Again, fine, fine, fine… but does this mean that the audience member cannot be surprised? That they cannot have their expectation confounded? (Incidentally, I think the problem with our reasoning here is that we’re assuming, and implicitly positing, intentionality as knowable, and as a significant (perhaps primary) ingredient in thinking about expectations; we’re to some extent still thinking about communication or expression.)
I’d argue that all improvisation must, by definition, at least allow the possibility of the redefinition of idioms. That the act of improvisation negates, kicks around, or opens up, the black box of the idiom. Although I think a performer can be idiom-conscious and improvise at the same time, I don’t believe they are bound by it. I like to think that audiences of improvisation don’t come to be spectators at an authorization ceremony, but are witnesses to a, at a bare minimum, mild shakeup.

What’s surprising is not that improvisation can confound the chain of expectations, but that, for example, Pulitzer Prize winning neo-classicists can consistently fulfill them ;-)

Derek Bailey, himself probably the best known proponent of the ‘non-idiomatic’ moniker, remarked that the difference between free and idiomatic improvisation depends on the former’s ability to “renew and change the known and so provoke an open-endedness which by definition is not possible in idiomatic improvisation” (Bailey, 1992, Improvisation: Its Nature and Practice in Music, London: British Library National Sound Archive, p. 142). Yet, in earlier in the same book, acknowledged that improvisation in general is “the sap through which music renews and reinvigorates itself” (ibid. p. 28). Does this mean that even Bailey saw that idiomatic improvisation could be, at times, free?; that it might, on occasion, not be idiomatic at all?